The new Scrambler RT 20 from Mountain Hardwear isn’t the most feature-packed backpack that you’ll find on the market today. Taking a quick glance at its specifications, you’ll find that it doesn’t have a lot of pockets for keeping your gear organized, nor does it come equipped with a suspension system, hydration sleeve, or even well-padded shoulder straps and hipbelt. In fact, when looking at the bag the word “spartan” seems to be the best way to describe it. But, dig a bit deeper and you’ll discover a pack that does its job very well and is surprisingly comfortable to wear, even when carrying a heavy load.

Made from Mountain Hardwear’s proprietary OutDry fabrics, the Scrambler RT 20 was designed to be a drybag that you can wear like a backpack. As such, it features a roll-top closure system that works in conjunction with the waterproof fabrics to keep moisture from ever reaching the interior of the bag. The company claims that it has tested the pack in a rainroom for as many as 24 hours, and at the end of that session no water managed to find its way inside. We can’t personally verify those claims, but we did put the Scrambler to the test the in the notoriously foul weather of the Southern Ocean, and can attest to its ability to keep your valuables safe from elements – even when its snowing and raining sideways.

As its name implies, the Scrambler RT 20’s main compartment offers 20 liters of capacity (MH says that it is actually 21-liters), which ought to be enough to carry most of the gear you’ll need for a day out on the trail. In order to maintain the waterproof integrity of the bag however, Mountain Hardwear chose not to incorporate any other organizational pockets of any kind on the pack. There are two handy stash pockets located on either side of the exterior however, which are perfect for holding a water bottle or other small items you might want to access quickly.

Beyond that, there aren’t a lot of other features to tell you about. The Scrambler does come equipped with trekking pole loops, which are always a welcome addition, and when the roll-top is closed, it makes a handy grab handle too. But other than that, it is a simple, lightweight (13.7 ounces) pack that has been purpose-built for use in wet, demanding environments.

Despite the fact that the Scrambler lacks serious padding in its shoulder straps and hipbelt, it is surprisingly comfortable to wear. We weighed the pack down with extra layers of clothing, winter mountaineering gloves, a water bottle, heavy camera equipment, and various other accessories, and than set out on a series of challenging hikes. Despite climbing up and down some incredibly steep hills in slick, wet conditions, the bag carried its load with ease, and wasn’t even prone to sliding around while scrambling over difficult terrain. That’s not something you can say about a lot of other full-featured daypacks, let alone one that is waterproof.

On that subject, if you’re in the market for a waterproof bag for hiking, paddling, mountain biking, or just commuting to the office, the Scrambler RT 20 is a great option. Our test model went through some seriously demanding conditions, and handled it all like a champ. Not a single drop of water ever made it to the inside of the bag, which is very reassuring when you find yourself facing adverse conditions. The fact that the pack is also lightweight and is easily packable makes it a good choice as a secondary bags for travelers too.

The Scramber RT 20 runs $110. The same pack is also available in 30, 35, and 40-liter versions as well. Find out more at mountainhardwear.com.